get the seller to provide a receipt stating that he grants you full, and exclusive, rights to this software and that he has removed it from his machine.
You should not be blocked when you register it, but you have some proof at least of your/their good intentions
I am interested in buying a USED Final Cut Pro 5 (Suite 1), mainly because I do not have the $$ (being a college student) to buy the new FCP Suite 2. When I register this software, will I be blocked, or are there any other things that can go wrong? I have a new iMac 10.5.1... and the dude that I'm buying from says that it is deleted off of his system. Thoughts?